this is the kind of crap people sell for 2750 Euros (don't know the current going rate but that's over 3200$ for sure) as being a performance rebuild...apart from the bubba job (paint resto and obviously eveything's been sandblasted...coming back yo haunt you), the cheap parts and general cheap and crummy look of things...there's something terribly wrong..who sees it?

http://www.speurders.nl/show_photo.p..._photo_count=3

 

Looks like the top of the piston is above the deck.

 

look closer you're warm

 

Piston is in up-side down.

 

Yea well actually he swapped left and right bank with them being upside down as a result (just turning them will result in the valve pockets being positioned wrong)

 

I didn't know the pistons were different on each side. I learn something everyday on this forum.

TT what would happen to the engine if fired up this way?

 

not all pistons are different for each side, some w/ 2 the same reliefs can be used on both sides (like the L82 piston) making sure the valve relief is on the intake side and for the 4 valve relief pistons they can be used in both pos. on each cyl. but keep the mark pointing to the front of the engine. if the reliefs are the same size, it depends on the type of piston.

What would happen? the valve would smack the piston.

 

I think that re-classifies that engine as a no performance engine.

With that kind of an amature job I believe I would have to suspect everything else in that engine.

I have another question. It appears that the matting sufaces at the water pump and the exhaust manifold were painted as well as inside the exhaust ports. Is that a bad thing too?

 

Well apart from it looking half assed it's not anything that will cause problems, the paint in the exhaust ports will burn off on startup, the paint on the wp and exhaust flange won't impede gasket sealing.

 

you do know that the arrow tells you which way the piston goes because of rod offset right? the hole in the piston is offset from center. if you turn it around you will lose some clearance inside the block and with certain valve reliefs. but i know alot of old timers that swear turning them around changes the angle of the rod, pushing on the crank, thus creating more torque. i also remember a problem chevy had in the early 90's that had something to do with this. ??

 

yes I know, that's why the some w/ the 4 valve relieds have the notch/mark, otherwise there would be no telling which way they had to go in on the bank you are installing it on, the ones w/ 2 valve reliefs or 1 big one don't need it because you can't have it upside down (unlike the guy who built the engine above)
However, the pistons w/ 4 valve reliefs or the ones w/ 2 symmetrical or 1 large valve relief (like the L82 piston) and no marking/notch can be installed in all bores in either positions and are not designed for a light and heavy thrust face...that's what it's for, the trust face.

So simple rule,
4 reliefs no marking -> anywhere
2 symmetrical reliefs or one big symmetrical one and no marking -> anywhere as long as the relief is on the manifold side
2 asymmetrical or 1 large asymmetrical, then you have large relief left: 2,3,6&7 and large relief on the right go to 1,4,5&8 with the relief on the manifold side and they should not be mixed.

BTW, the thrust side is also the reason for the 180degree difference in ring gap spacing between 1,3,5,7 and 2,4,6,8 .

 

The full story is that the pistons were/are not made so the rod is in the center of the piston, causing an offset and keeping the piston from rocking back and forth in the cylinder. This also causes a certain amount of drag in the cylinder and is the reason that you dont hear a tapping when the engine is cold. In the past the pistons were swapped from left bank to right bank to change the geometry of the rod angle causing it to push the piston in a way that caused it to ride straight up and down the bore freeing up a minimal amount of HP. This is more pronounced in mopars than any other due to the offset in them. The upside is that you could get free HP, I have personally seen as much as 17HP from a Big Block Mopar with this done and no other changes (was modidied before piston swapping). The downside is that when cold the engine will knock like its about to toss a rod till it warms up, due to the piston rocking. I dont know for sure which engine Chevy did this with but it was a crate engine and the knocking was a issue that people who baught them had with them. The most HP gain I have seen in a Chevy is 9HP in one of my own 350 vette (L82) engines. The engine was modified some before the swap.